How to issue Mushak 6.3 VAT invoices from your ERP

Every VAT-registered business in Bangladesh has to hand the buyer a tax invoice in the prescribed form, Mushak 6.3, at the time of supply. Most shops know this. Fewer know how much of the monthly return depends on that one document being right, and how many hours a month are lost when the challan is typed in Word, numbered by hand and filed in a box. This guide explains what the 6.3 is, what must be on it, how it feeds the 6.1, 6.2 and 9.1, and how an ERP takes the manual work out of it.

This is general guidance based on the VAT and Supplementary Duty Act 2012 and the rules under it. Rates, thresholds and forms change with the Finance Act and NBR circulars, so confirm specifics with your VAT consultant or the NBR VAT Online Service before relying on them.

What Mushak 6.3 is

Mushak 6.3 is the tax invoice, often called the VAT challan, that a registered supplier issues to the buyer when taxable goods or services are supplied. The form is prescribed under the VAT and SD Rules 2016. It does three jobs at once: it tells the buyer how much VAT they paid (and lets a registered buyer claim input tax credit), it becomes a line in your sales register, and it becomes the evidence an NBR officer asks for during an audit.

Businesses under the registration threshold that pay turnover tax instead of VAT have a lighter regime, but once you are VAT registered, the 6.3 applies to your taxable sales, including retail sales at the counter. Retailers in some sectors use NBR-approved electronic fiscal devices or sales data controllers rather than a paper challan; if that applies to you, the same data still has to be captured and kept.

What must appear on a Mushak 6.3

The prescribed form has a fixed layout. In general terms it requires the following, and the table shows where an ERP takes each field from so that nothing is typed twice.

Field on the 6.3	Where SORS ERP takes it from
Your registered name, address and BIN	Company profile, entered once
Sequential challan number	Mushak numbering series, issued automatically
Date and time of issue	The moment the sale is finalised
Buyer name, address and BIN if registered	Customer record; walk-in customers are recorded as such
Delivery address, and vehicle details where goods are transported	Delivery or sales order
Description of goods or services, unit and quantity	Item master and the invoice lines
Unit price and value excluding VAT	Price list or POS price
Supplementary duty rate and amount where applicable	Tax structure on the item
VAT rate and VAT amount per line	Tax rate on the item (standard 15%, or the reduced or truncated rate for that sector)
Total value including all taxes	Calculated
Name, designation and signature of the person responsible	User who finalised the sale, printed on the form

Two points cause the most trouble in practice. First, numbering has to be sequential and unbroken; a gap invites questions. Second, the VAT rate must be right per item, not per invoice, because a computer shop that sells hardware at the standard rate and a service at a different rate needs both on one challan.

How 6.1, 6.2 and 9.1 relate

The 6.3 is one form in a family. The forms that matter for most trading businesses are these.

Form	What it is	Where the data comes from
Mushak 6.1	Purchase register: every purchase with the supplier’s challan details	Finalised purchase bills and goods receipts
Mushak 6.2	Sales register: every sale and the tax on it	Every issued 6.3
Mushak 6.3	Tax invoice issued to the buyer at supply	Each sale
Mushak 6.7 and 6.8	Credit note and debit note for returns and price changes after the invoice	Sales returns and adjustments, never edits to the original
Mushak 6.10	Statement of purchases and sales above ৳2 lakh per transaction	Filtered from the registers
Mushak 9.1	Monthly VAT return	Summarised from 6.1, 6.2 and adjustments

The logic is simple once you see it: the 6.3 you issue becomes a row in your 6.2; the 6.3 your supplier issues becomes a row in your 6.1; the 9.1 is the difference between the two, with adjustments. If the registers are built automatically from the same records as the invoices, the return reconciles by construction. If they are typed separately, they will disagree, and you will spend the last week of the month finding out why.

How automation works in SORS ERP

In SORS ERP the Mushak forms are not a separate module you feed data into; they are generated from the sales and purchase records that already exist.

1. Set your BIN, registered address and Mushak numbering series in the company settings. Set the VAT rate, and any supplementary duty, on each item or item category, so the right rate follows the item onto every invoice.
2. Record the customer once, with their BIN if they are registered, so their input credit is protected and you never re-type their address.
3. Make the sale as normal, from the sales module or the POS counter. Stock is deducted and the accounting entries are posted at the same time through mapping rules.
4. Finalise the invoice. The ERP assigns the next challan number, stamps the date and time, and generates the Mushak 6.3 as a PDF for printing, emailing or sending as a link.
5. Handle changes properly. If a customer returns goods or a price is corrected, raise a sales return or adjustment, which gives your accountant the reference for the credit or debit note; the original 6.3 is never edited.
6. At month end, open the period summary. The 6.1 register and the VAT return summary are already populated from the period’s purchases and sales. Review, then pass the figures to whoever files the 9.1 on the NBR online system. The ERP has a submit, approve, reject and cancel workflow so an accountant can review before anything is locked.
7. Lock the period once filed, so nobody can back-date a sale into a month that has already been returned.

SORS ERP prepares the figures and the registers. Filing the return itself is done on the NBR system by you or your consultant; we do not claim a direct connection to NBR.

Keeping records for five years

The Act requires books, invoices and related records to be preserved for at least five years. On paper that is five years of boxes. In an ERP it means three things: the PDF of every 6.3 is stored and searchable by number, date or customer; the registers can be exported to Excel for any past period; and you should take periodic backups or exports of your own data, whoever hosts the system. Ask any vendor how you would get five years of challans out if you stopped using them. The reports module in SORS ERP keeps an export history so you can see what was pulled, by whom and when.

Common mistakes

• Issuing the challan from Word or Excel and typing the number by hand, then discovering a duplicate or a gap at audit.
• Putting one VAT rate on the whole invoice when the items carry different rates.
• Editing an issued invoice instead of raising a credit note, so the register no longer matches what the customer holds.
• Recording a registered buyer as a walk-in customer, which denies them input credit and creates a dispute later.
• Missing the supplier’s BIN or challan number on purchases, which weakens your own input credit claim in the 6.1.
• Changing software without carrying the numbering series forward, so the sequence restarts mid-year.
• Leaving periods open so a sale entered late lands in a month that has already been returned.

None of these are exotic. They are what happens when the invoice, the register and the return are three separate documents maintained by three separate people.

Where SORS ERP fits

SORS ERP generates Mushak 6.3 from every finalised sale and Mushak 6.1 from purchases, builds the VAT return and turnover tax summaries, and keeps the numbering, period locks and five-year history in one place. It is a young product from a company founded in 2024, and it does not file to NBR directly; it prepares accurate registers so your accountant or consultant can. If your business needs sector-specific forms such as 6.4 for contract manufacturing, ask us during the demo rather than assuming.

To see a 6.3 generated from a sale on your own item list, request a demo.

Written by the team that builds SORS ERP, the ERP described on this site. We implement it ourselves in Bangladesh, so the guidance here comes from setups we run rather than from general research. More about SORS Technology.

How to issue a Mushak 6.3 tax invoice from SORS ERP

1. Set up your VAT details once. Enter your BIN, registered address and Mushak numbering series in company settings, and assign the VAT rate and any supplementary duty to each item or item category so the right rate follows the item onto every invoice.
2. Record the customer. Create the customer with name, address and BIN if they are registered, so registered buyers keep their input tax credit and you never re-type their details.
3. Make the sale. Create the invoice from the sales module or the POS counter. Stock is deducted and the accounting entries are posted at the same time.
4. Finalise and print the 6.3. Finalise the invoice. SORS ERP assigns the next challan number, stamps the date and time and generates the Mushak 6.3 as a PDF to print, email or share as a link.
5. Handle returns without editing the original. For a return or price correction, raise a sales return or adjustment, which gives the reference for a credit or debit note. Never edit an issued 6.3.
6. Review the month and lock the period. Open the period summary, review the 6.1 register and the return summary, pass the figures to whoever files the 9.1 on the NBR system, then lock the period.

Frequently asked questions

Do I need to issue a Mushak 6.3 for every sale, including small counter sales?

If you are VAT registered, taxable supplies require a tax invoice at the time of supply, and that includes retail sales. Some retail sectors use NBR-approved electronic fiscal devices instead of a printed 6.3, and businesses under the registration threshold that pay turnover tax follow a lighter regime. Confirm which applies to you with your VAT consultant.

Can a POS receipt serve as the Mushak 6.3?

Only if it carries the prescribed content: your name, address and BIN, a sequential challan number, date and time, item description, quantity, value, VAT rate and amount, and the total. An ERP that generates the 6.3 from the POS sale, rather than printing a separate slip, meets this. A plain till receipt with a total and a VAT line usually does not.

What if I need to change an invoice after the 6.3 is issued?

Do not edit the issued invoice. Raise a sales return or adjustment, which gives you the reference for a credit note (Mushak 6.7) or debit note (Mushak 6.8) against the original. This keeps your sales register consistent with the document the customer holds.

How long must Mushak 6.3 invoices be kept?

The VAT and SD Act requires records, including tax invoices and registers, to be preserved for at least five years. Storing the PDF of every 6.3 in the ERP and taking your own periodic exports satisfies this more reliably than paper, provided you keep backups.

Does SORS ERP file the VAT return with NBR?

No. SORS ERP generates the 6.3 and 6.1, keeps the numbering and period summaries, and prepares the return summary with a review and approval workflow. Filing the 9.1 on the NBR online system is done by you or your consultant using those figures.